docs: def _continuous_colormap(hue, cmap, vmin, vmax):
      """
      Creates a continuous colormap.
  
      Parameters
      ----------
      hue : iterable
          The data column whose entries are being discretely colorized. Note that although top-level plotter ``hue``
          parameters ingest many argument signatures, not just iterables, they are all preprocessed to standardized
          iterables before this method is called.
      cmap : ``matplotlib.cm`` instance
          The `matplotlib` colormap instance which will be used to colorize the geometries.
      vmin : float
          A strict floor on the value associated with the "bottom" of the colormap spectrum. Data column entries whose
          value is below this level will all be colored by the same threshold value. The value for this variable is
          meant to be inherited from the top-level variable of the same name.
      vmax : float
          A strict ceiling on the value associated with the "top" of the colormap spectrum. Data column entries whose
          value is above this level will all be colored by the same threshold value. The value for this variable is
          meant to be inherited from the top-level variable of the same name.
  
      Returns
      -------
      cmap : ``mpl.cm.ScalarMappable`` instance
          A normalized scalar version of the input ``cmap`` which has been fitted to the data and inputs.
      """
      mn = min(hue) if vmin is None else vmin
      mx = max(hue) if vmax is None else vmax
      norm = mpl.colors.Normalize(vmin=mn, vmax=mx)
      return mpl.cm.ScalarMappable(norm=norm, cmap=cmap)